<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>01_js的三种引入方式</title>
    <link rel="stylesheet" href="">
    <style>

    </style>
</head>
<body>
<button onclick="alert(123)">
    点击即玩
</button>
<button onclick="console.log('点我干嘛')">
    点我干嘛
</button>
<div id="aaa">123</div>
<script src="01.js">
  console.log('我是js代码');
  console.log(aaa);
</script>
<script>
    console.log('我是js代码');
    console.log(aaa);
</script>
</body>
</html>